SUMMARY OF INVESTMENTS (Maturities) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Trading, Amortized Cost
Amortized Cost	$ 11,277	$ 14,582
Trading, Fair Value
Fair Value	13,240	$ 16,842
Continuing and Discontinuing Operations
Available-For-Sale, Amortized Cost
Due in one year or less	48,331
Due after one year through five years	225,816
Due after five years through 10 years	544,551
Due after 10 years	691,968
Available-For-Sale, Fair Value
Due in one year or less	48,492
Due after one year through five years	226,069
Due after five years through 10 years	542,662
Due after 10 years	684,274
Trading, Amortized Cost
Due in one year or less	4,408
Due after one year through five years	5,019
Due after five years through 10 years	0
Due after 10 years	1,850
Trading, Fair Value
Due in one year or less	5,232
Due after one year through five years	5,872
Due after five years through 10 years	0
Due after 10 years	2,136
Fixed maturities \| Continuing and Discontinuing Operations
Available-For-Sale, Amortized Cost
Securities not categorized by contractual maturity	1,761,289
Available-For-Sale, Fair Value
Securities not categorized by contractual maturity	1,749,488
Trading, Amortized Cost
Amortized Cost	11,277
Trading, Fair Value
Fair Value	13,240
Asset-backed securities \| Continuing and Discontinuing Operations
Available-For-Sale, Amortized Cost
Securities not categorized by contractual maturity	3,256
Available-For-Sale, Fair Value
Securities not categorized by contractual maturity	3,495
Mortgage-backed securities \| Continuing and Discontinuing Operations
Available-For-Sale, Amortized Cost
Securities not categorized by contractual maturity	7,642
Available-For-Sale, Fair Value
Securities not categorized by contractual maturity	7,424
Collateralized mortgage obligations \| Continuing and Discontinuing Operations
Available-For-Sale, Amortized Cost
Securities not categorized by contractual maturity	239,725
Available-For-Sale, Fair Value
Securities not categorized by contractual maturity	$ 237,072

Trading Securities, Debt Maturities, after Five Through Ten Years, Amortized Cost Basis

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